Donya Zare - Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
Hossein Fazeli - Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
Sharareh Moghim - Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

Background: Nosocomial infections are one of the most leading cause of morbidity and mortality in patients with cancer.The emergence of multiple-drug-resistant (MDR) strains of Gram-negative bacteria causing nosocomial infection has become a serious concern in cancer patients. Therefore, the present study aimed to determine the spectrum and antibiotic resistance pattern of Gram-negative bacteria related nosocomial infections among Iranian cancer patients. Methods: This descriptive cross-sectional study was conducted during the 6 months period from December 2015 to May 2016 in two tertiary care centers located in Isfahan and Arak Province.Gram-negative bacteria obtained from different clinical specimens from hospitalized patients withcancer and were identified using standardmicrobiological methods.Antibiotic susceptibility pattern wasdetermined by the disk diffusion method according to the CLSI recommendation. Results: Of totally 259 culture positive cases, E. coli showed the highest isolation rate (60.6%) followed by K. pneumonia (26.6%) and Proteus spp. (11.2%). The rate of MDR isolates were 91.5% (237/259). Overall, the most frequent source of bacterial isolation was urinary tract infection (65.6%) followed by skin and soft tissue infection (23.6%). The antibiotic susceptibility results showed meropenem and ceftazidime as the most effective antibiotics for E.coli, K. pneumonia and Proteus spp. isolates. Moreover, meropenem was the most effective antibiotic against MDR isolates. Conclusion: Our findings showed a significant distribution of MDR Gram-negative bacteria which may increase the burden of healthcare-associated infections in cancer patients. Although, carbapenem can be considered as effective agents toward MDR strains for empirical antibiotic therapy in our region.

Nosocomial infection, Antibiotic resistance, Enterobacteriaceae, Cancer